Improvement in friction-clutches



UNITED STATES PATENT Orrron.

GEORGE H. STARBUOK, OF TROY, NEW YORK.

IMPROVEMENTIN FRlCTlQN-CLUTCHES.

Specification forming part of Letters Patent No. 159,464, dated February2, 1875; application filed January 18, 1875.

To all whom it may concern:

Be it known that I, GEORGE H. STARBUOK, of Troy, in the county ofRensselaer and State of New York, have invented certain new and usefulImprovements in Friction-Clutches, of which the following is aspecification:

The object of the present invention is to provide a simple and efiectivefriction-brake, to be used in connection with hoisting mechanism ordriving pulleys or wheels, which are designed to be connected to ordisconnected from a driving-shaft.

The invention consists,first, in an improved combination and arrangementof devices for forcing segmental friction blockslor surfaces against theconverge friction-rim of ahoisting drum or pulley, by which an equalstrain is brought to bear. on both inner sides of the rim, the devicesfor operating the frictionblocks consisting of arms of an equal orunequal length, which are pivoted to the block at their outer ends, andto a cross-key, carried by a sliding rod or bolt, at their inner ends,the arms so arranged forming a knuckle-joint, and the cross-keyprojecting through and moving in a longitudinal slot forward in the drumor pulley-shaft.

The invention further consists in the employment of guides for themovable frictionblocks, said guides being located or attached near theperiphery of the driving wheel or pulley, so as to cause thefriction-blocks to be forced against the friction-rim without torsion orstrain on the shaft, said wheel being provided with stops for limitingthe inward motion of the friction-blocks, said stops being so located onthe driving wheel or pulley as to prevent the drawback all coming on onesegment in case of adhesion of either segment to the rim, and equalizingthe distance the segments are carried from the friction-rim.-

The invention further consists in attaching the friction-block orsegment-shifting lever to an arm, which is formed with or attached to aswiveled sleeve or yoke fitted on a collar on the drum-shaft, the end ofthe lever being secured to a sleeve fitted loosely between collars onthe rod or bolt which forms the connection- With the knuckle-jointdevices.

In the accompanying drawings, Figure 1 is an end elevation of ahoisting-drum and driving-wheel having my invention applied thereto.Fig. 2 is a side view of the same. Fig. 3 is a transverse section takenthrough the friction-rim of the hoisting-drum. Fig. 4 is a longitudinalsection of the entire apparatus. Figs. 5 and 6 illustrate modificationsof devices for operating the friction-blocks or segments.

A designates a shaft, with journals at each end, which are fitted insuitable boxes 12 of the frame-work c. A large spur-wheel, B, or plaindriving-pulley, is mounted on said shaft A, and issecuredthereto by aset-screw, or

by a key, as may be preferred. An ordinary hoisting-drum, G, is alsofitted loosely on the shaft, and it is provided with a friction-rim, D,at the end adjoining the driving wheel or pulley, against which rim thefriction-blocks or segments E are forced when it is desired to clutchthe drum and wheel together. The friction-blocks are of a segmentalform, and are provided with peripheral seats for the reception of afilling, F, of wood, leather, or soft metal, forming a surface to comein frictional contact with the rim D. The segments or friction-blocksare guided and held from moving awayfrom the driving-wheel B by means ofguides Gr, cast with and forming part of the wheel. These guides arelocated near the periphery of the wheel, and they are grooved for thereception of the reduced ends of the segments or friction-blocks.provided with a central bore, which terminates at or about the inner endof the friction-rim of the hoisting-drum, said bore being designed forthe reception of a pin or bolt, H, which is slotted at its inner end toallow the passage through it of a cross-key, I, moving in a slot orelongated centrally-located opening, J, in the shaft A. To each end ofthe cross-key there is jointed an arm, K, the other end of the arm beingjointed to the segment. The

arms K are made in two parts, connected and made continuous by the nutL, which has a right-hand thread at one end, and a left-hand thread atthe other end, by which the arms may be lengthened or shortened, asdesired. The segment or clutch shifting or operating lever M is pivotedto a curved arm, N, which projects from a sleeve or swiveled yoke, O,encircling a collar, P, on the end of the shaft The shaftA is A. 'Saidyoke or lever holder is made in two parts, joined together by flangesand bolts, and it is loose on the shaft, so as to permit the same toturn without carrying the lever around. Q R are collars fitting on theprojecting end of the pin or bolt H, the inner one, Q, being secured toand forming part of the pin, and the outer collar, It, being loose, butprevented from moving endwise by a nut, S, applied to the screw-threadedend of the pin. The inner bifurcated end of the lever is journaled tothe loose collar B, so as to enable it to be turned to the right orleft.

Rotating motion is imparted to the driving spur-wheel or pulley, as thecase may be, and when the clutch-lever is in the position shown in thedrawin gs-that is, thrown in an inward direction -the friction-clu tchesare held tightly against the friction-rim of the hoisting-drum, thuscausing the same to be rotated with the shaft. By moving the leverforward or outward, the jointed arms or knuckle-joints are caused toassume an oblique position, and the friction-surfaces removed fromcontact with the rim of the drum. To secure an equal movement of thesegments in an inward direction, pins to a: are inserted in, or stopsmay be applied to, the arms of the drivingwheel, which stops, by comingin contact with the friction-blocks, will limit the movement of thesame.

The principal object attained by the present invention is the dispensalof a sleeve or thimble sliding on the drum-shaft, and forming part ofthe clutch-block-operating mechanism,

this being rendered possible by the provision of the toggle or knucklejointed arm connected directly with a crosskey on a sliding bolt or pinconnected with the shifting-lever, said key moving in a slot in theshaft, so as to allow a continuous or connected joint from one rim tothe other.

Another point of advantage derived by my invention is the positivemotion of the clutch mechanism toward or from the friction-rim of thedrum, a spring for releasing the clutch being dispensed with.

Several modifications of the invention, as above described, will readilysuggest themselves, as, for example, the driving wheel or pulley may bemade to run loosely upon the shaft, and the rim for theadjustablesegments to bear against may be cast on said wheel. The hoistingdrum orpulley is in thisinstance fastened to the shaft, and the driving-guidesaffixed to it, and used for the same purpose as when applied to thedrivingwheel.

Another modification consists in pivoting the connecting-arms KKtogether at the central point of the shaft, as shown in Figs. 5 and 6,connecting the sliding-bolt H directly to the same.

It will be observed that the cross-key I is capable of a movementendwise, whereby it is only necessary to tighten up the nut L on one ofthe arms, which will make that arm a trifle longer than the one on theopposite side; consequently it is not essential to operate all the armstogether, and hence much time is saved in adjusting the parts.

I claim as my invention 1. A friction-clutch having a cross-key, I,formingalink-connection between the knucklejoints or armsK K, carryingthe friction-blocks E, in combination with the slotted and axiallyboredshaft of the hoisting-drum, sliding rod H, lever M, and collar N,substantially as described.

2. The hoistingdrum 0, having friction-rim D and a slotted andaxially-bored shaft, in combination with a gear-wheel, B, having theguides G, and with friction-blocks E, sliding rod, and a lever connectedtherewith, substantially as described.

3. Thedriving-wheel constructed with guides G and stops X, for guidingand limiting the motion of the clutch and friction-blocks as the clutchmechanism is brought in and out of gear, substantially as described.

4. In combination with the hoisting-drum and slotted and axially-boredshaft, the lever M, pivoted upon the divided collar through its yoke,and connected with the end of the sliding rod, for operating the armscarrying the friction-blocks, substantially as described. 1

In testimony that I claim the foregoing I have hereunto set my hand.

GEORGE H. STARBUOK.

Witnesses:

GEo. A. STONE, CHARLES S. ANDREWS.

